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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

42862 results found.

  1. GRB060930: Faulkes Telescope South observation
  2. GRB 060930: Xinglong TNT optical observations
  3. GRB 060929: Further XRT Refined Analysis
  4. GRB 060929: Swift/UVOT Optical Observations
  5. GRB 060930: ROTSE-III Optical Limits
  6. GRB 060930: A long X-ray rich GRB detected by INTEGRAL
  7. GRB 060927 : GAO 150cm telescope optical observation
  8. GRB060929: Swift-XRT refined analysis.
  9. GRB 060929, Swift-BAT further refined analysis - late-time flare
  10. GRB 060929, Swift-BAT refined analysis
  11. GRB060929: Optical limit
  12. GRB 060929: MASTER-VWF-Kislovodsk observations
  13. GRB 060929: BOOTES-IR & OSN observations
  14. GRB 060929: Swift detection of a burst
  15. GRB060908: optical observations
  16. GRB 060729: An update on the late-time Swift observations
  17. GRB 060927: Spectroscopic redshift z=5.6
  18. IBAS Alert n.3501: not a GRB
  19. IBAS Alert n.3500: not a GRB
  20. GRB060923C: optical limit
  21. GRB060927: optical observations
  22. GRB 060926: Swift-UVOT UVW1 Detection Retraction
  23. GRB 060927: Early color
  24. GRB 060927: Swift XRT Team refined analysis
  25. GRB 060927 optical limit
  26. GRB 060927, Swift-BAT refined analysis
  27. GRB 060927: Xinglong TNT optical observations
  28. GRB060926: improved redshift
  29. GRB 060927: Possible host galaxy (star?) in the SDSS
  30. GRB 060927 : Kiso optical observation
  31. GRB060927: Faulkes Telescope South observation
  32. GRB 060926: MASTER: first minutes decay
  33. GRB060927 - SDSS Pre-Burst Observations
  34. GRB 060927: optical afterglow confirmation
  35. GRB 060927A: ROTSE-III Detection of Optical Counterpart
  36. Swift XRT boresight
  37. GRB 060927: Swift detection of a burst
  38. GRB060926: VLT redshift
  39. GRB 060926: Swift-UVOT Detections
  40. GRB 060923A: Schedule of Spitzer Space Telescope Observations
  41. GRB 060926: OPTIMA-Burst -- further observations
  42. GRB 060926: Swift XRT refined analysis
  43. GRB 060926, Swift-BAT refined analysis
  44. GRB 060923A: Radio Observations
  45. GRB 060912A: Redshift of probable host galaxy
  46. GRB 060926: Watcher observations
  47. GRB060926 OPTIMA-Burst optical observation
  48. GRB 060926: Swift detection of a burst
  49. GRB 060923C, Swift-BAT refined analysis
  50. GRB 060923C: VLA Observation
  51. GRB 060923C: NIR afterglow confirmed
  52. GRB060923C: AROMA optical obsevation
  53. GRB 060923C: Gemini Observations and Afterglow Candidate
  54. GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
  55. GRB 060923C: VLT J-band observations
  56. GRB060923B: Swift/UVOT upper limits
  57. GRB 060923B: Swift XRT Refined Analysis
  58. GRB 060923C: Swift XRT refined analysis
  59. GRB 060923A: Swift XRT refined analysis
  60. GRB 060923C: Keck Observations
  61. GRB 060923A: Keck and Gemini Observations
  62. GRB 060923C: Xinglong TNT optical observations
  63. GRB 060923B, Swift-BAT refined analysis
  64. GRB060923C: Faulkes Telescope North optical observations
  65. GRB 060923C: Swift detection of a burst
  66. GRB 060923B: Swift detection of a burst
  67. GRB 060923, Swift-BAT refined analysis
  68. GRB 060923: Early Super-LOTIS Observations
  69. GRB 060923: UKIRT nIR observations - candidate afterglow
  70. GRB060923: Faulkes Telescope North optical observations
  71. GRB060923 - SDSS Pre-Burst Observations
  72. GRB 060923: KAIT observations
  73. GRB 060923: Swift detection of a burst
  74. Swift detection of IGR J17497-2821 (trigger 230504)
  75. Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
  76. GRB060919: Swift/UVOT optical observations
  77. GRB 060919 : Faulkes South Telescope Observations
  78. GRB 060919, Swift-BAT refined analysis
  79. GRB060919: XRT refined analysis
  80. GRB 060919: TAROT optical observations
  81. GRB 060919: Swift detection of a burst
  82. GRB 060912A: VLA Observation
  83. GRB 060912A: Probable Host Galaxy
  84. IBAS Alert n.3470: not a GRB
  85. GRB060825: MAGIC telescope GeV observation
  86. Konus-Wind observation of GRB 060912
  87. IBAS Alert No.3468: not a GRB
  88. GRB 060912: Redshift of nearby 2MASS galaxy
  89. GRB060912: optical observations
  90. GRB 060912B: Watcher observations
  91. GRB060912: Swift/UVOT Observations
  92. GRB060912: OPTIMA-Burst optical observations
  93. GRB 060912B: a long GRB detected with INTEGRAL
  94. GRB 060912: Swift XRT Team Refined Analysis
  95. GRB 060912, Swift-BAT refined analysis
  96. GRB 060912: Correction to GCN 5559
  97. GRB 060912: Swift detection of a burst with an optical afterglow
  98. GRB060906: Danish/DFOSC optical observations
  99. VLA observations of GRB 060908
  100. GRB 060908: redshift

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